Improvement in the preparation of white oxide of zinc for use in paints



UNITED STATES PATENT OFFICE. I

one. 1!. Lew s, or PHILADELPHIA, PENNSYLVANlAm IMPROVEMENT IN THEPREPARATION OF WHITE OXIDE 0F ZINC FOR USE IN PAINTS.

Specification forming part of Letters Patent No. 36,4 14, datedSeptember 9, 1862.

To all whom it may concern: I

Be it known that I, GEORGE T. LEWIS, of

the city of Philadelphia, in the countyof Philadelphia and State of'Pennsylvania, have invented a new and useful Improvement in thePreparation of White Oxide of Zinc for the Manufacture of Paint; andI-do hereby declare that the following is. a full, clear, and

--exact description of thesame.

Zinc-whi e paint is ordinarily manufactured- H byIgrinding the whiteoxideof zinc in oil without any previous preparation beyond levigation,and its want of what is termed by paintters body has been muchcomplained of.

The object of my invention is to enable the white oxide of zinc to bemanufactured into paint having a desirable degree of body; and

to this end my invention consists in subject, ing it in its dry state tothe combined actions of friction and pressure, by which means its bulkis greatly reduced and itis enabled to be ground with a much smallerquantity of oil.

oil. With a pair of chasers of fifty-one inches diameter and fourteeninches wide, making fourteen revolutions per minute, I have operatedsuccessfully upoutwo hundred pounds at once, continuing the operationfor thirty minutes, in which time I have reduced it nearly toonehalf'its original bulk, a barrel which held one hundred andseventy-five pounds in the original uncondensed state holding three Ihundred and forty-five pounds of that which had been condensed. Theoxidein-it's original uncondensed state required for grinding two andone-half gallons of oil for every one'hun'- "tired-pounds; but whencondensed it only required' for grinding one and three-fourths gallon.Bysubjecting the oxide to the operation of the chaser-s for a greaterlength of time it maybe more highly condensed and ground with a lessquantity of" oil, and increased body will be thus given to the paint.

I do not claim broadly the application of pressure as shown inTittertons English patent of November 4', 1856 but What I claim'as myinvention,and desire to secnreby Letter Patents, i's--.

The preparation of white oxide of zinc for the manufacture of paint bysubjecting it; to thecombined actions of friction and press- ,ure,substantially as herein described, whereby its density is increased andthe paint caused 'to have greater body.

GEORGE 'r. LEWIS.

Witnesses:

"JAs. MILLIGAN, J12,

:J 01m '1. LEWIS.

